Snowmobiles are well known in the art. They usually have a relatively long seat that allow the snowmobiles to be ridden by two people: a driver and a passenger. This, combined with the fact that snowmobiles are relatively wide and provided with a heavy gasoline powered engine, make the conventional snowmobile a relatively bulky recreational vehicle.
To overcome this bulkiness of the conventional snowmobile, many single seater snowmobile type recreational vehicles have been designed.
U.S. Pat. No. 5,474,146 issued to Yoshioka et al. on Dec. 12, 1995 and entitled "Snow Vehicle" describes such a single seater recreational vehicle. Yoshioka's snow vehicle has a motorcycle upper structure where a steered front ski replaces the conventional front wheel and an engine-driven endless belt track assembly replaces the rear wheel. While the snow vehicle described in this document arguably offers better handling over conventional snowmobiles since it is lighter and narrower, it also has a major drawback: instability. Indeed, since the weight of the driver is applied to the vehicle between the front ski and the endless track, i.e. close to the fork, and since the vehicle's seat is far from the ground, is it argued that Yoshioka's snow vehicle is inherently instable, the center of gravity being far from the ground and towards the front of the vehicle. This instability is increased by the fact that the endless track contacts the ground on a relatively short portion of the entire length of the vehicle.
The following United States Patents also describe similar single seater snowmobile type recreational vehicles having similar drawbacks:
Number Inventor Issue Date 4,613,006 Moss et al. September 23, 1986 5,064,208 Bibollet November 12, 1991 Des. 333,110 Mogi et al. February 9, 1993
Indeed, the recreational vehicles shown in these documents all share the common motorcycle type steering assembly that positions the driver relatively in the front portion of the vehicle, which leads to instability, as discussed hereinabove.
U.S. Pat. No. 5,568,840 issued on Oct. 29, 1996 to Nagata et aL. describes a snowmobile where the driver is standing on a step floor. Instability is also a major drawback of Nagata's snowmobile since the center of gravity of the snowmobile, while in use, is far from the ground.